Stain treating composition

ABSTRACT

A multi-compartment liquid dispenser comprising first and second liquid containing compartments, wherein present in at least one compartment is a first component that generates a gas upon the mixing of the liquid contents of the first and second compartments and a second component that foams when gas is generated by the first component and the foam subsequently quickly breaks.

This invention relates to an improved process for the removal of stainsfrom surfaces, preferably from fabric, and to compositions used in suchprocesses.

EP 0745 665, WO 0100765 and WO 0012672 describe products that containtwo liquids that are intended for cleaning. Upon mixing the twocomponents produce an effervescent effect that alongside the surfactantspresent produce a foam.

WO 9731095 describes an apparatus for claiming surfaces that containstwo liquids that are mixed upon delivery to the surface. The firstliquid contains a hydrohalite bleach. The second liquid has a chelatingagent or a builder. The pH on mixture of the two liquids is about 11.

We have found that although an effervescent effect may be desirable andadd to the cleaning performance a persistent foam may have severalnon-beneficial effects. Firstly it may be difficult to rinse away andsecondly the foam may obscure the stain removing performance from theuser.

We have found that by providing in either or both of the two separatecompositions [mixed during, before or after (preferably during orbefore) application] with a quick breaking foam forming component theabove problems are overcome.

We present as a feature of the invention a multi compartment liquiddispenser comprising first (a) and second (b) liquid containingcompartments, wherein present in at least one compartment is a firstcomponent that generates a gas upon the mixing of the liquid contents ofthe first and second compartments and a second component that foams whengas is generated by the first component and subsequently the foamquickly breaks.

Preferably the product is used for stain removal at a surface, ideally afabric surface. Preferably the surface is a fabric surface, such as anitem of clothing, linen or carpet. Ideally the fabric surface is acoloured fabric.

We present as a further feature of the invention a process for stainremoval at a surface comprising applying to that surface a mixture of atleast two aqueous compositions, wherein present in at least one of thecompositions is a first component that generates a gas upon the mixingof the liquid content of the first and second compartments and a secondcomponent that foams when gas is generated by the first component andthen subsequently the foam quickly breaks.

Quick Breaking Foam

Preferably the foam breaks within 5 minutes of formation after mixing,ideally less than 5, 4, 3, 2, or 1 minute. Preferably the foam does notbreak for at least 10 seconds, 20 seconds, 30 seconds, 1, 2 or 3minutes. By the use of the term “break or breaks” we mean that at least50% of the volume of foam generated by the mixing of component (a) and(b) has disappeared without any form of physical or chemicalintervention.

Preferred surfactant to achieve this effect are those selected frombelow, and include mixtures thereof, preferably they are hydophilic,i.e. their hydrophilic/lipohilic balance HLB is greater than 10.

Anionic Surfactant

Preferred anionic surfactants capable of producing a breaking foam areethoxylated alkyl sulfates of the formula:RO(C₂H₄O)_(n)SO₃ ⁻M⁺

-   -   wherein R is a C₈-C₂₀ alkyl group, preferably C₁₀-C₁₈ such as a        C₁₂-C₁₆, n is at least 4, for example from 4 to 20, preferably 4        to 9, especially 4 to 6, and M is a salt-forming cation such as        lithium, sodium, potassium, ammonium, alkylammonium or        alkanolammonium.        Nonionic Surfactants

Preferred nonionic surfactants capable of producing a breaking foam arefatty alcohol ethoxylates, especially those of formula:R(C₂H₄O)_(n)OH

-   -   wherein R is a straight or branched C₈-C₁₆ alkyl group,        preferably a C₉-C₁₅, for example C₁₀-C₁₄, alkyl group and n is        at least 4, for example from 4 to 16, preferably 4 to 12, more        preferably 4 to 10.

Preferably the HLB value is greater than 9, ideally greater than 10.

Examples of fatty alcohol ethoxylates are those made from alcohols of 12to 15 carbon atoms and which contain about 7 moles of ethylene oxide.Such materials are commercially marketed under the trademarks Neodol25-7 and Neodol 23-6.5 by Shell Chemical Company.

An additional or alternative group of preferred nonionic surfactants arethe polyoxyalkylated non-ionics of formula:R¹O[CH₂CH(R³)O]_(X)[CH₂]_(k)CH(OH)[CH₂]_(j)OR²

-   -   wherein R¹ and R² represent linear or branched chain, saturated        or unsaturated, aliphatic or aromatic hydrocarbon groups with        1-30 carbon atoms (presently 1 to 10) or one of R¹ and R² may be        a hydrogen, R³ represents a hydrogen atom or a methyl group, x        is a value between 2 and 30 and, k and j are values between 1        and 12, preferably between 1 and 5. R¹ and R² are preferably        linear or branched chain, saturated or unsaturated, aliphatic or        aromatic hydrocarbon groups with 6-22 carbon atoms, where group        with 8 to 18 carbon atoms are particularly preferred.        Particularly preferred values for x are comprised between 2 and        20, preferably between 4 and 15.

When x=2 or 3, the group R³ could be chosen to build ethylene oxide(R³═H) or propylene oxide (R³=methyl) units which can be used in everysingle order for instance (PO) (EO)(EO), (EO)(PO)(EO), (EO)(EO)(PO),(EO)(EO) (EO), (PO) (EO) (PO), (PO) (PO) (EO) and (PO)(PO)(PO). Thevalue 2 or 3 for x is only an example and bigger values can be chosenwhereby a higher number of variations of (EO) or (PO) units would arise.

Alternatively when x=2 or 3, the group R³ could be chosen to buildethylene oxide (R³=H) or propylene oxide (R³=methyl) units which can beused in every single order for instance (EO)(EO)(EO), (PO)(PO)(PO),(PO)(EO)(PO), (EO)(PO)(EO), (PO)(PO) and (EO)(EO). The value 2 or 3 forx is only an example and bigger values can be chosen whereby a highernumber of variations of (EO) or (PO) units would arise.

Particularly preferred polyoxyalkylated alcohols of the above formulaare those where k=1 and j=1 originating molecules of simplified formula:R¹O[CH₂CH(R³)O]_(X)CH₂CH(OH)CH₂OR².

A suitable example is Biodac 232, available from Condea or Berol 185from Akzo Nobel.

Gas Generation

In one preferred embodiment of the invention an effervescent effect isachieved upon mixing (a) and (b). The effervescent component typicallycomprises two agents to react to generate gas. Preferably one agentcomprises an effervescent base, preferably present at a level of fromabout 1% to about 10%, more preferably from about 2% to about 5% byweight of the compositions of the present invention. Preferably theother effervescent agent is an acid.

Suitable effervescent bases are selected from carbonates, bicarbonates,sesquicarbonates and mixtures thereof. Preferably, the base is selectedfrom the group consisting of sodium carbonate, potassium carbonate,lithium carbonate, magnesium carbonate, calcium carbonate, ammoniumcarbonate, mono-, di-, tri- or tetra-alkyl or aryl, substituted orunsubstituted, ammonium carbonate, sodium bicarbonate, potassiumbicarbonate, lithium bicarbonate, magnesium bicarbonate, calciumbicarbonate, ammonium bicarbonate, mono-, di-, tri- or tetra-alkyl oraryl, substituted or unsubstituted, ammonium bicarbonate and mixturesthereof.

The most preferred bases are selected from the group consisting ofsodium bicarbonate, monoethanol-ammonium bicarbonate and mixturesthereof.

In another preferred embodiment, one effervescent agent preferablycomprises a peroxide reducing enzyme that is preferably held withincomponent (b), such as peroxidase, laccase, dioxygenase and/or catalaseenzyme, preferably catalase enzyme, preferably present at a level offrom about 0.001% to about 10%, more preferably, from about 0.01% toabout 5%, even more preferably from about 0.1% to about 1%, mostpreferably from about 0.1% to about 0.3% by weight of the compositionsof the present invention. The other effervescent agent is preferably,hydrogen peroxide. Catalase enzyme is commercially available fromBiozyme Laboratories under the trade name Cat-lA, which is a bovineliver derived catalyse enzyme; from Genencor International under thetrade name Oxy-Gone 400, which is a bacterial derived catalyse enzyme;and from Novo Nordisk under the trade name Terminox Ultra 50L.

According to the invention there is provided a process for stain removalat a surface, comprising applying to that surface a mixture of at leasttwo aqueous compositions:

-   -   (a) an aqueous composition comprising having a pH of greater        than 0 but less than 7 [hereinafter component (a)] and    -   (b) an aqueous composition comprising an effervescent base and        wherein component (a), (b) or both (a) and (b) contains a        component that foams and then quickly breaks upon the mixing        of (a) and (b).        Preferably component (a) and/or component (b) additionally        comprise at least one surfactant or water-soluble polymer.        Preferably component (a) contains a source of active oxygen.        Preferably component (b) contains at least one enzyme.        pH        The pH of component (a) is preferably less than 7, ideally less        than 6.5, 5.0, 4.5, 4.0, 3.5 or 3.0. Ideally the pH is at least        1.0, 1.5, 2.0 or 2.5.        The pH of component (b) is preferably greater than 7, ideally        greater than 7.5, 8.0, 8.5, 9.0, 9.5 or 10.0. Ideally the pH is        less than 13.0, 12.5, 12.0 or 11.5. The pH of either (a) or (b)        can be adjusted by the addition of a suitable acid or base.        Alkalising Agent

Preferably component (b) contains an alkalising agent. An alkalisingagent is a compound or mixture of compounds that can increase the pH ofthe resultant mixture of (a) and (b) to a pH of >8.0,ideally >8.5, >9.0, >9.5 or >10.0. Preferably the alkalising agentproduces a pH of <11.0 or <10.5. The alkalising agent ideally comprisesa base. Suitable bases are selected from carbonates, bicarbonates,sequicarbonates, hydroxides, and silicates.

Therefore, the pH of component (b) is preferably higher than the pH ofcomponent (a).

Preferably component (b) contains an alkalising agent. An alkalisingagent is a compound or mixture of compounds that can increase the pH ofthe resultant mixture of (a) and (b) to a pH of >8.0,ideally >8.5, >9.0, >9.5 or >10.0. Preferably the alkalising agentproduces a pH of <11.0 or <10.5. The alkalising agent ideally comprisesa base. Suitable bases are selected from hydroxides, carbonates,bicarbonates, sequicarbonates, hydroxides, and silicates.

Therefore, the pH of component (b) is preferably higher than the pH ofcomponent (a).

Ideally, an alkaline buffering means is also present. An alkalinebuffering means at a level of from 0.1% to 10% by weight of component(b). Preferably, component (b) herein comprise from 0.2% to 8% by weightof the total composition of a pH buffering means or a mixture thereof,preferably from 0.3% to 5%, more preferably from 0.3% to 3% and mostpreferably from 0.3% to 2%.

By “alkaline buffering means”, it is meant herein any compound whichwhen mixed with component (a) makes the resulting solution able toresist an increase in hydrogen ion concentration.

Preferred alkaline buffering means for use herein comprise an acidhaving its pK (if only one) or at least one of its pKs in the range from7.5 to 12.5, preferably from 8 to 10, and its conjugated base.

pK is defined according to the following equation:pK=−logKwhere K is the Dissocation Constant of the weak acid in water andcorresponds to the following equation:[A][H]/[HA]=Kwhere HA is the acid and A is the conjugated base.

Preferably the alkaline buffering means herein consists of the weak acidand its conjugate base at a weight ratio of the weak acid to itsconjugate base of preferably 0.1:1 to 10:1, more preferably 0.2:1 to5:1. Highly preferred ratio of the weak acid to its conjugate base is 1since this is the best combination to achieve optimum bufferingcapacity.

Preferably a given pH buffering means herein will be used to buffercompositions having a pH between pH=pK−1 and pH=pK+1 of each of its pK.

Suitable pH buffers are formed from acid addition salts of bases thathave a pKb within 1 unit of the pH of component (b). Suitable bufferingsystems are selected from: carbonate/bicarbonate, citric acid/citrates,borate/boric acid or phosphates/phosphoric acid or any other buffersystems described in literature.

Preferably component (a) does not have a pH buffer present. Ideally onlycomponent (b) has a pH buffer.

Sources of Active Oxygen

The use of oxygen bleaches with or without enzymes in compositions forstain removal has been known for a long time and many such compositionsare available.

However a common difficulty in formulating such a composition is toensure that the bleach remains stable during storage but is sufficientlyactive on use. This is particularly difficult to achieve in liquidcompositions.

One solution has been to formulate liquid peroxygen bleaches at pHsbetween about 3 and 7 to produce a stable composition, but suchcompositions do not provide sufficient bleaching power to be useful formany household situations. Attempts have therefore also been made toformulate liquid peroxygen bleach compositions at pHs above this rangeto improve their performance. However these generally require expensivestabilising compounds to prevent loss of activity after manufacture.

Enzymes are a common component of stain treating compositions. Enzymeslose their cleaning performance in presence of a strong oxidant, such ashydrogen peroxide at alkaline pH. Surprisingly, we have found that bythe inclusion of a surfactant or a water-soluble polymer in either orboth of the separate compositions, (preferably present in at least theenzyme composition or both compositions) excellent cleaning performanceis achieved. Whilst not wishing to be bound by theory, it is believedthat the activity of the enzyme is maintained for a longer period afterthe peroxide composition is mixed with the enzyme composition by theprotective effects of surfactant micelles formed in the mixture.

An essential ingredient is a source of active oxygen. A preferred sourceaccording to the present invention is hydrogen peroxide or sourcesthereof. As used herein a hydrogen peroxide source refers to anywater-soluble source of hydrogen peroxide. Suitable water-solublesources of hydrogen peroxide for use herein include percarbonates,organic or inorganic peroxides and perborates.

Hydrogen peroxide or sources thereof provide from 0.1% to 15%,preferably from 0.5% to 10%, most preferably from 1% to 5% by weight ofthe total composition of active oxygen in said composition.

As used herein active oxygen concentration refers to the percentageconcentration of elemental oxygen, with an oxidation number zero, thatbeing reduced to water would be stoichiometrically equivalent to a givenpercentage concentration of a given peroxide compound, when the peroxidefunctionality of the peroxide compound is completely reduced to oxides.The active oxygen sources according to the present invention increasethe ability of the compositions to remove oxidisable stains, to destroymalodorous molecules and to kill germs.

The concentration of available oxygen can be determined by methods knownin the art, such as the iodimetric method, the permanganometric methodand the cerimetric method. Said methods and the criteria for the choiceof the appropriate method are described for example in “HydrogenPeroxide”, W. C. Schumo, C. N. Satterfield and R. L. Wentworth, ReinholdPublishing Corporation, New York, 1955 and “Organic Peroxides”, DanielSwern, Editor Wiley Int. Science, 1970.

Suitable organic and inorganic peroxides for use in the compositionsaccording to the present invention include diacyl and dialkyl peroxidessuch as dibenzoyl peroxide, dilauroyl peroxide, dicumyl peroxide,persulphuric acid and mixtures thereof. The compositions according tothe present invention comprise from 0% to 15%, preferably from 0.005% to10%, by weight of the total composition of said organic or inorganicperoxides.

Suitable preformed peroxyacids for use in the compositions according tothe present invention include diperoxydodecandioic acid DPDA, magnesiumperphthalatic acid, perlauric acid, perbenzoic acid, diperoxyazelaicacid and mixtures thereof. The compositions according to the presentinvention comprise from 0% to 15%, preferably from 0.005% to 10%, byweight of the total composition of said preformed peroxyacids.

Optionally, the compositions may additionally comprise from 0% to 30%,preferably from 2% to 20% of peracid precursors, i.e. compounds thatupon reaction with hydrogen peroxide product peroxyacids. Examples ofperacid precursors suitable for use in the present invention can befound among the classes of anhydrides, amides, imides and esters such asacetyl triethyl citrate (ATC) described for instance in EP 91 87 0207,tetra acetyl ethylene diamine (TAED), succinic or maleic anhydrides.

Additional Surfactant

Preferably, the surfactant is found at levels of 0.1 to 25% wt, ideallyfrom 1 to 10% w and may be found in (a), (b) or both (a) and (b),preferably at least in (b).

Ideally sufficient total surfactant is present in each composition (a)or (b) or (a) and (b), such that upon mixture of (a) and (b) thecritical micelle concentration (CMC) is reached, i.e. the level abovewhich the formation of micelles occurs [typically measured by a changein physical properties, i.e. turbidity or conductivity].

Preferably non-ionic surfactants are used. Examples of non-ionicsurfactants are fatty acid alkoxylates, such as fatty acid ethoxylates,especially those of formula:R(C₂H₄O)_(n)OHwherein R is a straight or branched C₈-C₁₆ alkyl group, preferably aC₉-C₁₅, for example C₁₀-C₁₄, alkyl group and n is at least 1, forexample from 1 to 16, preferably 2 to 12, more preferably 3 to 10.

The alkoxylated fatty alcohol non-ionic surfactant will frequently havea hydrophilic-lipophilic balance (HLB) which ranges from 3 to 17, morepreferably from 6 to 15, most preferably from 7 to 13.

Examples of fatty alcohol ethoxylates are those made from alcohols of 12to 15 carbon atoms and which contain about 7 moles of ethylene oxide.Such materials are commercially marketed under the trademarks Neodol25-7 and Neodol 23-6.5 by Shell Chemical Company. Other useful Neodolsinclude Neodol 1-5, an ethoxylated fatty alcohol averaging 11 carbonatoms in its alkyl chain with about 5 moles of ethylene oxide; Neodol23-9, an ethoxylated primary C₁₂-C₁₃ alcohol having about 9 moles ofethylene oxide; and Neodol 91-10, an ethoxylated C₉-C₁₁ primary alcoholhaving about 10 moles of ethylene oxide.

Alcohol ethoxylates of this type have also been marketed by ShellChemical Company under the Dobanol trademark. Dobanol 91-5 is anethoxylated C₉-C₁₁ fatty alcohol with an average of 5 moles ethyleneoxide and Dobanol 25-7 is an ethoxylated C₁₂-C₁₅ fatty alcohol with anaverage of 7 moles of ethylene oxide per mole of fatty alcohol.

Other examples of suitable ethoxylated alcohol non-ionic surfactantsinclude Tergitol 15-S-7 and Tergitol 15-S-9, both of which are linearsecondary alcohol ethoxylates available from Union Carbide Corporation.Tergitol 15-S-7 is a mixed ethoxylated product of a C₁₁-C₁₅ linearsecondary alkanol with 7 moles of ethylene oxide and Tergitol 15-S-9 isthe same but with 9 moles of ethylene oxide.

Other suitable alcohol ethoxylated non-ionic surfactants are Neodol45-11, which is a similar ethylene oxide condensation products of afatty alcohol having 14-15 carbon atoms and the number of ethylene oxidegroups per mole being about 11. Such products are also available fromShell Chemical Company.

Further non-ionic surfactants are, for example, C₁₀-C₁₈ alkylpolyglycosides, such as C₁₂-C₁₆ alkyl polyglycosides, especially thepolyglucosides. These are especially useful when high foamingcompositions are desired. Further surfactants are polyhydroxy fatty acidamides, such as C₁₀-C₁₈ N-(3-methoxypropyl)glycamides and ethyleneoxide-propylene oxide block polymers of the Pluronic type.

The surfactant can also be an anionic surfactant. Such anionic surfaceactive agents are frequently provided in a salt form, such as alkalimetal salts, ammonium salts, amine salts, aminoalcohol salts ormagnesium salts. Contemplated as useful are one or more sulfate orsulfonate compounds including: alkyl sulfates, alkyl ether sulfates,alkylamidoether sulfates, alkylaryl polyether sulfates, monoglyceridesulfates, alkylsulfonates, alkylamide sulfonates, alkylarylsulfonates,olefinsulfonates, paraffin sulfonates, alkyl sulfosuccinates, alkylether sulfosuccinates, alkylamide sulfosuccinates, alkylsulfosuccinamate, alkyl sulfoacetates, alkyl phosphates, alkyl etherphosphates, acyl sarconsinates, acyl isethionates, and N-acyl taurates.Generally, the alkyl or acyl radical in these various compounds comprisea carbon chain containing 12 to 20 carbon atoms.

Particularly preferred are alkyl sulphate anionic surfactants. Mostpreferred are the non-ethoxylated C₁₂₋₁₅ primary and secondary alkylsulphates, especially sodium lauryl sulfate.

In yet another aspect of the present invention, an effervescent systemcomprising an effervescent agent-containing component, preferably abase, is within component (b), such that when mixed with the acidic pHof component (a) generates effervescence.

Enzyme

Enzymes are a common component of stain treating compositions. Enzymeslose their cleaning performance in presence of a strong oxidant, such ashydrogen peroxide at alkaline pH. Surprisingly, we have found that bythe inclusion of a surfactant or a water-soluble polymer in either orboth of the separate compositions, (preferably present in at least theenzyme composition or both compositions) excellent cleaning performanceis achieved. Whilst not wishing to be bound by theory, it is believedthat the activity of the enzyme is maintained for a longer period afterthe peroxide composition is mixed with the enzyme composition by theprotective effects of surfactant micelles formed in the mixture.

Where present said enzymes are preferably selected from cellulases,hemicellulases, peroxidases, proteases, gluco-amylases, amylases,xylanases, lipases, phospholipases, esterases, cutinases, pectinases,keratanases, reductases, oxidases, phenoloxidases, lipoxygenases,ligninases, pullulanases, tannases, pentosanases, malanases,beta-glucanases, arabinosidases, hyaluronidase, chondroitinase, laccaseor mixtures thereof.

Preferred enzymes include protease, amylase, lipase, peroxidases,cutinase and/or cellulase.

The cellulases usable in the present invention include both bacterial orfungal cellulase. Preferably, they will have a pH optimum of between 5and 12 and an activity above 50 CEVU (Cellulose Viscosity Unit).Suitable cellulases are disclosed in U.S. Pat. No. 4,435,307,JP-A-61078384 and WO-A-96/02653 which disclose fungal cellulasesproduced respectively from Humicola insolens, Trichoderma, Thielavia andSporotrichum. EP-A-739 982 describes cellulases isolated from novelBacillus species. Suitable cellulases are also disclosed inGB-A-2.075.028; GB-A-2.095.275; DE-OS-2.247.832 and WO-A-95/26398.

If present, cellulases are normally incorporated in the detergentcomposition at levels from 0.0001% to 2% of active enzyme by weight ofthe detergent composition.

Peroxidase enzymes are used in combination with oxygen sources, e.g.percarbonate, perborate, persulfate, hydrogen peroxide, etc. They areused for “solution bleaching”, i.e. to prevent transfer of dyes orpigments removed from substrates during wash operations to othersubstrates in the wash solution. Peroxidase enzymes are known in theart, and include, for example, horseradish peroxidase, ligninase andhaloperoxidase such as chloro- and bromo-peroxidase.Peroxidase-containing detergent compositions are disclosed, for example,in WO-A-89/099813, WO-A-89/09813 and in EP-A-540784. Also suitable isthe laccase enzyme.

If present, peroxidases are normally incorporated in the detergentcomposition at levels from 0.0001% to 2% of active enzyme by weight ofthe detergent composition.

Other preferred enzymes that can be included in the detergentcompositions of the present invention include lipases. Suitable lipaseenzymes for detergent usage include those produced by microorganisms ofthe Pseudomonas group, such as Pseudomonas stutzeri ATCC 19.154, asdisclosed in GB-A-1,372,034. Suitable lipases include those which show apositive immunological cross-reaction with the antibody of the lipase,produced by the microorganism Pseudomonas fluorescent IAM 1057. Thislipase is available from Amano Pharmaceutical Co. Ltd., Nagoya, Japan,under the trade name Lipase P “Amano,” hereinafter referred to as“Amano-P”. Other suitable commercial lipases include Amano-CES, lipasesex Chromobacter viscosum, e.g. Chromobacter viscosum var. lipolyticumNRRLB 3673 from Toyo Jozo Co., Tagata, Japan; Chromobacter viscosumlipases from U.S. Biochemical Corp., U.S.A. and Disoynth Co., TheNetherlands, and lipases ex Pseudomonas gladioli. Especially suitablelipases are lipases such as Ml Lipase™ and Lipomax™ (Gist-Brocades) andLipolase™ and Lipolase Ultra™ (Novo) which have found to be veryeffective when used in combination with the compositions of the presentinvention. Also suitables are the lipolytic enzymes described inEP-A-258068, WO-A-92/05249, WO-A-95/22615, WO-A-94/03578, WO-A-95/35381and WO-A-96/00292.

Also suitable are cutinases [EC 3.1.1.50] which can be considered as aspecial kind of lipase, namely lipases which do not require interfacialactivation. Addition of cutinases to detergent compositions have beendescribed in e.g. WO-A-88/09367; WO-A-90/09446, WO-A-94/14963 andWO-A-94/14964.

The lipases and/or cutinases are normally incorporated in either or bothcomposition at a level from 0.0001% to 2% of active enzyme by weight ofthe composition.

Suitable proteases are the subtilisins which are obtained fromparticular strains of B. subtilis and B. licheniformis (subtilisin BPNand BPN′). One suitable protease is obtained from a strain of Bacillus,having maximum activity throughout the pH range of 8-12, developed andsold as ESPERASE™ by Novo Industries A/S of Denmark, hereinafter “Novo”.The preparation of this enzyme and analogous enzymes is described inGB-A-1,243,784 to Novo. Other suitable proteases include ALCALASE™,DURAZYM™ and SAVINASE™ from Novo and MAXATASE™, MAXACAL™, PROPERASE™ andMAXAPEM™ (protein engineered Maxacal) from Gist-Brocades. Proteolyticenzymes also encompass modified bacterial serine proteases, such asthose described in EP-A-292623 (particularly pages 17, 24 and 98), andwhich is called herein “Protease B”, and in EP-A-199,404, which refersto a modified bacterial serine protealytic enzyme which is called“Protease A” herein. Suitable is what is called herein “Protease C”,which is a variant of an alkaline serine protease from Bacillus in whichlysine replaced arginine at position 27, tyrosine replaced valine atposition 104, serine replaced asparagine at position 123, and alaninereplaced threonine at position 274. Protease C is described inWO-A-91/06637. Genetically modified variants, particularly of ProteaseC, are also included herein.

High pH protease are preferred, such as from Bacillus sp. NCIMB 40338described in WO-A-93/18140. Enzymatic detergents comprising protease,one or more other enzymes, and a reversible protease inhibitor aredescribed in WO-A-92/03529. When desired, a protease having decreasedadsorption and increased hydrolysis is available as described inWO-A-95/07791. A recombinant trypsin-like protease for detergentssuitable herein is described in WO-A-94/25583. Other suitable proteasesare described in EP-A-516,200.

The proteolytic enzymes are incorporated in either or both compositionsat a level of from 0.0001% to 2%, preferably from 0.001% to 0.2%, morepreferably from 0.005% to 0.1% pure enzyme by weight of the composition.

Amylases (alpha and/or beta) can be included for removal ofcarbohydrate-based stains. WO-A-94/02597 describes cleaning compositionswhich incorporate mutant amylases. See also WO-A-95/10603. Otheramylases known for use in cleaning compositions include both alpha- andbeta-amylases. alpha-Amylases are known in the art and include thosedisclosed in U.S. Pat. No. 5,003,257; EP-A-252,666; WO-A-/91/00353;FR-A-2,676,456; EP-A-285,123; EP-A-525,610; EP-A-368,341; andGB-A-1,296,839. Other suitable amylases are stability-enhanced amylasesdescribed in WO-A-94/18314 and WO-A-96/05295 and amylase variants havingadditional modification in the immediate parent available from NovoNordisk A/S, disclosed in WO-A-95/10603. Also suitable are amylasesdescribed in EP-A-277,216, WO-A-95/26397 and WO-A-96/23873.

Examples of commercial alpha-amylases products are Purafect Ox Am™ fromGenencor and Termamyl™, Ban™, Fungamyl™ and Duramyl™, Natalase™ allavailable from Novo Nordisk A/S Denmark. WO-A-95/26397 describes othersuitable amylases: alpha-amylases characterised by having a specificactivity at least 25% higher than the specific activity of Termamyl™ ata temperature range of 25 DEG C. to 55 DEG C. and at a pH value in therange of 8 to 10, measured by the Phadebas™ alpha-amylase activityassay. Suitable are variants of the above enzymes, described inWO-A-96/23873. Other amylolytic enzymes with improved properties withrespect to the activity level and the combination of thermostability anda higher activity level are described in WO-A-95/35382.

Preferred amylase enzymes include those described in WO-A-95/26397 andin co-pending application by Novo Nordisk PCT/DK96/00056.

The amylolytic enzymes are incorporated in either or both compositionsat a level of from 0.0001% to 2%, preferably from 0.00018% to 0.06%,more preferably from 0.00024% to 0.048% pure enzyme by weight of thecomposition.

Polymer

Suitable polymers are those that are water-soluble and includepolycarboxylate polymer (such as those that can be purchased by Rohm andHaas under the Acusol 445N name) and polycarboxylic acid copolymers(such as can be purchased under the Sokalan CP9 name by BASF).

Compositions suitable for carrying out the invention may be provided asseparate components suitable for mixing by the consumer. Where thecompositions are suitable for mixing they may be mixed either directlyat the surface or remote from the surface before application.

Component (a) preferably comprises hydrogen peroxide or peracetic acid.

In accordance with the invention the two components (a) and (b) may bemixed in any suitable proportions, depending upon their initialconcentrations, suitably such that the finally applied mixture comprises0.01-30% w/w of hydrogen peroxide or an organic peracid. Preferably, theratio of component (a) to component (b) is from 10:1 to 1:10, mostpreferably from 2:1 to 1:2, ideally 0.8:1 to 1:0.8.

It is preferred that the two components (a) and (b) are mixed no morethan 10 minutes before application to the surface requiring stainremoval.

It is most preferred that the two components (a) and (b) are mixed atthe surface requiring stain removal, so that the improved stain removaleffect may occur immediately.

In this aspect component (a) may be applied to the surface followed bycomponent (b) or vice versa. Alternatively (and preferably) components(a) and (b) are applied to the surface substantially simultaneouslywithin 30 seconds.

According to a preferred embodiment of the presentation invention, theconcentration of hydrogen peroxide or organic peracid in the compositionimmediately after mixing is from 0.01 to 10% w/w. This would mean forexample in a 1:1 mix of component (a) and (b) that component (a) priorto the mixing would contain from 0.02 to 20% w/w of hydrogen peroxide oran organic peracid.

Where component (a) comprises hydrogen peroxide it is most preferredthat the concentration of hydrogen peroxide in the mixture immediatelyafter mixing should be from 1.5 to 5% w/w. For example, if a 1:1 mixtureof components (a) and (b) is to be mixed, then component (a) shouldcomprise from 3 to 10% w/w hydrogen peroxide.

The concentration of the enzyme in component (b) will be less than 1%wt.

The process of the present invention alleviates the need to use furtherstabilising components for the hydrogen peroxide/organic peracid whenpreparing commercial products. In addition enzyme activity is maintainedfor longer periods upon storage and in use.

The components suitable for use in the process according to theinvention may further include any other auxiliary ingredients—known tothe art. Ideally such auxiliary ingredients are selected from;fragrance, dye, sequesterant, chelating agent, germicide, preservative,corrosion inhibitor, antioxidant or a mixture of any thereof.

The above auxiliary ingredients may be included at concentrations offrom 0.01% w/w to 10% w/w. These auxiliary ingredients may be includedin either component (a), or component (b) or both if appropriate.

Compositions suitable for use in the process according to the presentinvention may be stored in any appropriate containers known to the art.For example, the two components may be stored in two-compartment packssuitable for sequential or simultaneous dispensing.

Preferably both components (a) and (b) are liquids, most preferably theymay be stored in a two-compartment dispenser, one compartment containingeach component and the dispenser being adapted to dispense eachcomponent on to a surface, either sequentially or, preferably,simultaneously.

Containers

Containers that have at least two compartments are disclosed in theprior art. An example of a two chamber squeezy dispenser is disclosed inUS 5765725. An example of a gravity driven two chamber dispensing systemis disclosed in WO 0185595. An example of a spray dispenser having twoliquid compartments is disclosed in EP 0479451.

EXAMPLES

The invention will now be illustrated by the following Examples.

Example 1

% wt First chamber Water 71.8 Hydrogen peroxide 50% 14 Citric Acid 50%10 Chelating Agent 1 Sodium hydroxide 50% 3.2 Total 100.0 Second chamberWater 73.58 Dowicil 75 0.050 Sodium borate decahydrate 0.514 Trisodiumcitrate 1.3 Copolymer dispersant(25%) 0.200 Enzyme 0.44 Sodiumbicarbonate 4 Propylene glycol 4 Berol 185 15 Acusol 0.7 Perfume 0.21Total 100

Example 2

% wt First chamber Water 71.8 Hydrogen peroxide 50% tech 14 Citric Acid50% 10 Pentasodium DTPA 40% 1 Sodium hydroxide 50% 3.2 Total 100 Secondchamber Water 73.586 Dowicil 75 0.05 Sodium borate decahydrate 0.514Trisodium citrate 1.3 Dispersant Polymer (25%) 0.2 Enzyme 0.44 Sodiumbicarbonate 4 Propylene glycol 4 Berol 185 15 Acusol (45%) 0.7 Perfume0.21 Total 100

1. A multi-compartment liquid dispenser comprising first and secondliquid containing compartments, wherein present in at least onecompartment is a first component that generates a gas upon the mixing ofthe liquid contents of the first and second compartments and a secondcomponent that foams when gas is generated by the first component andthe foam subsequently quickly breaks.
 2. A dispenser according to claim1 wherein hydrogen peroxide or an acid is present in the firstcompartment.
 3. A dispenser according to claim 2 wherein an effervescentagent is present in the second compartment.
 4. A dispenser according toclaim 3 wherein the effervescent agent is an effervescent base or aperoxide reducing enzyme.
 5. A dispenser as according to claim 1 whereinthe pH of one of said first or second liquid containing compartments ishigher than the pH of the other of said first or second liquidcontaining compartments.
 6. A dispenser according to claim 5 wherein thefirst compartment does not contain a pH buffer.
 7. A dispenser accordingto claim 5 wherein the second compartment does contain a pH buffer.
 8. Adispenser according to claim 4 wherein the effervescent base is acarbonate or a bicarbonate.
 9. A dispenser according to claim 1 whereinthe second component contains a nonionic surfactant having an HLB ofgreater than
 10. 10. A process for stain removal at a surface comprisingapplying to that surface a mixture of at least two aqueous compositions,wherein present in at least one of the compositions is a first componentthat generates a gas upon the mixing of the liquid content of the firstand second compartments and a second component that foams when gas isgenerated by the first component wherein the foam subsequently quicklybreaks.